NEW YORK -- Osama bin Laden's son-in-law went on trial Wednesday in federal court in Manhattan, where jurors heard him portrayed both as a murderous mouthpiece for al Qaeda and as a target of a prosecution designed to play on fears and resentments from the Sept. 11, 2001, attacks.

In opening statements, Assistant U.S. Attorney Nicholas Lewin told the jury that bin Laden had summoned Sulaiman Abu Ghaith on the afternoon of Sept. 11, 2001, and asked him to use his oratory skills as the public face of al Qaeda to recruit and inspire recruits to attack the United States again. Abu Ghaith is the highest-ranking al Qaeda figure to face trial on U.S. soil since suicide attackers struck the city's twin towers.

"While our buildings still burned, he agreed ... in what is the most important moment in al Qaeda's savage history," Lewin said, showing jurors a photo of Abu Ghaith sitting side-by-side with bin Laden in Afghanistan on Sept. 12, 2001. "He invoked his twisted view of Islam and declared, 'Fight thee against the friends of Satan. Fight with al Qaeda against America."'

Defence attorney Stanley Cohen countered by pointing out that Lewin referenced the Sept. 11 attacks several times in his opening, even though his client wasn't involved in the plot.

"This is not Osama bin Laden," Cohen said, pointing to Abu Ghaith. "This is Sulaiman Abu Ghaith, a Muslim, an Arab from Kuwait, a husband, a father, an imam, a talker, an ideologue."

The defendant, who wore a suit and tie to court, listened through an Arabic interpreter and occasionally took notes.

Abu Ghaith, 48, a onetime imam at a Kuwaiti mosque, was brought to New York from Turkey last year. He has pleaded not guilty to charges he conspired to kill Americans after the Sept. 11 attacks and provided material support and resources to a terrorist organization. Born in Kuwait, he is married to bin Laden's eldest daughter, Fatima. According to Cohen, they were married in 2008 or 2009.

Prosecutors allege Abu Ghaith began his rise through the ranks for al Qaeda by becoming a motivational speaker at safe houses and training camps for aspiring jihadists in the weeks and months before Sept. 11. Afterward, bin Laden instructed him to lead recruitment efforts by appearing in widely distributed videos.

"For more than a year after, the defendant used the murderous power of his words to try to strengthen al Qaeda," Lewin said.

He quoted the defendant several times, including one remark he said came weeks after the attack: "These young men who have destroyed the United States and launched the storm of airplanes against it have done a good deed. The storm of airplanes will not abate."

The government contends the statements are evidence that Abu Ghaith had prior knowledge of the failed shoe-bomb airline attack by Richard Reid in December 2001 and another plot to down a flight from Paris to Miami with explosives hidden in shoes. Prosecutors are expected to introduce testimony via video feed of another former al Qaeda member in Great Britain who was in on the shoe-bomb plot.

Cohen told jurors that they might feel outrage over some of the "dumb" and "stupid" statements made by his client. But he urged jurors to keep open minds.

"At the end of the day, there's really no evidence," Cohen said. "There is the substitution for evidence with fright and alarm."

The first witness Wednesday was an FBI agent, James Fitzgerald, who travelled the world investigating al Qaeda before and after Sept. 11, 2001.

Through Fitzgerald's testimony in a trial expected to last a month, Assistant U.S. Attorney Michael Ferrara introduced numerous photographs and videos of Abu Ghaith sitting with bin Laden and other top al Qaeda leaders after the attacks.

Jurors watched as Abu Ghaith waved his arms to add emphasis as he spoke in Arabic in one video. They also saw a video in which bin Laden bragged that the attacks had caused the United States more than $1 trillion in losses to its economy. And they saw video of media interviews with bin Laden in the late 1990s in which he urged that Americans be killed anywhere in the world.

Prosecutors also displayed on courtroom monitors a February 1998 bin Laden fatwa in which he said the killing of "Americans and their allies, both civilian and military, is the individual duty of every Muslim able to do so."

Ferrara asked Fitzgerald whether the FBI's investigation into Sept. 11 had turned up any evidence that Abu Ghaith was involved.